diff --git a/partitioned-popins/partitioned-popins.permission-all.tentative.sub.https.window.js b/partitioned-popins/partitioned-popins.permission-all.tentative.sub.https.window.js
new file mode 100644
index 00000000000000..83eb092905c612
--- /dev/null
+++ b/partitioned-popins/partitioned-popins.permission-all.tentative.sub.https.window.js
@@ -0,0 +1,32 @@
+// META: script=/resources/testdriver.js
+// META: script=/resources/testdriver-vendor.js
+
+'use strict';
+
+// Spec: https://explainers-by-googlers.github.io/partitioned-popins/
+// Step 1 (window) Set up listener to resolve messages as they come in.
+// Step 2 (window) Open iframe for other origin.
+// Step 3 (iframe) Open partitioned popin.
+// Step 4 (popin) Cleanup.
+// Step 5 (iframe) Report success.
+// Step 6 (window) Cleanup.
+
+async_test(t => {
+  const id = String(Date.now());
+  // Step 1
+  window.addEventListener("message", t.step_func(e => {
+    switch (e.data.type) {
+      case 'popin':
+        // Step 6
+        assert_equals(e.data.message, "Success");
+        t.done();
+        break;
+    }
+  }));
+
+  // Step 2
+  const iframe = document.createElement("iframe");
+  iframe.allow = "popins";
+  iframe.src = "https://{{hosts[alt][]}}:{{ports[https][0]}}/partitioned-popins/resources/partitioned-popins.permissions-iframe.html";
+  document.body.appendChild(iframe);
+}, "Verify Partitioned Popins in an iframe work when the policy is *");
diff --git a/partitioned-popins/partitioned-popins.permission-all.tentative.sub.https.window.js.headers b/partitioned-popins/partitioned-popins.permission-all.tentative.sub.https.window.js.headers
new file mode 100644
index 00000000000000..36ba34ecd53462
--- /dev/null
+++ b/partitioned-popins/partitioned-popins.permission-all.tentative.sub.https.window.js.headers
@@ -0,0 +1 @@
+Permissions-Policy: popins=*
diff --git a/partitioned-popins/partitioned-popins.permission-default.tentative.sub.https.window.js b/partitioned-popins/partitioned-popins.permission-default.tentative.sub.https.window.js
new file mode 100644
index 00000000000000..613d8dbb5f2da2
--- /dev/null
+++ b/partitioned-popins/partitioned-popins.permission-default.tentative.sub.https.window.js
@@ -0,0 +1,31 @@
+// META: script=/resources/testdriver.js
+// META: script=/resources/testdriver-vendor.js
+
+'use strict';
+
+// Spec: https://explainers-by-googlers.github.io/partitioned-popins/
+// Step 1 (window) Set up listener to resolve messages as they come in.
+// Step 2 (window) Open iframe for other origin.
+// Step 3 (iframe) Open partitioned popin.
+// Step 4 (popin) Cleanup.
+// Step 5 (iframe) Report failure.
+// Step 6 (window) Cleanup.
+
+async_test(t => {
+  const id = String(Date.now());
+  // Step 1
+  window.addEventListener("message", t.step_func(e => {
+    switch (e.data.type) {
+      case 'popin':
+        // Step 6
+        assert_equals(e.data.message, "Failure");
+        t.done();
+        break;
+    }
+  }));
+
+  // Step 2
+  const iframe = document.createElement("iframe");
+  iframe.src = "https://{{hosts[alt][]}}:{{ports[https][0]}}/partitioned-popins/resources/partitioned-popins.permissions-iframe.html";
+  document.body.appendChild(iframe);
+}, "Verify Partitioned Popins in an iframe fails when the policy isn't set");
diff --git a/partitioned-popins/partitioned-popins.permission-self.tentative.sub.https.window.js b/partitioned-popins/partitioned-popins.permission-self.tentative.sub.https.window.js
new file mode 100644
index 00000000000000..5930442aa872d7
--- /dev/null
+++ b/partitioned-popins/partitioned-popins.permission-self.tentative.sub.https.window.js
@@ -0,0 +1,32 @@
+// META: script=/resources/testdriver.js
+// META: script=/resources/testdriver-vendor.js
+
+'use strict';
+
+// Spec: https://explainers-by-googlers.github.io/partitioned-popins/
+// Step 1 (window) Set up listener to resolve messages as they come in.
+// Step 2 (window) Open iframe for other origin.
+// Step 3 (iframe) Open partitioned popin.
+// Step 4 (popin) Cleanup.
+// Step 5 (iframe) Report failure.
+// Step 6 (window) Cleanup.
+
+async_test(t => {
+  const id = String(Date.now());
+  // Step 1
+  window.addEventListener("message", t.step_func(e => {
+    switch (e.data.type) {
+      case 'popin':
+        // Step 6
+        assert_equals(e.data.message, "Failure");
+        t.done();
+        break;
+    }
+  }));
+
+  // Step 2
+  const iframe = document.createElement("iframe");
+  iframe.allow = "popins";
+  iframe.src = "https://{{hosts[alt][]}}:{{ports[https][0]}}/partitioned-popins/resources/partitioned-popins.permissions-iframe.html";
+  document.body.appendChild(iframe);
+}, "Verify Partitioned Popins in an iframe fail when the policy is 'self'");
diff --git a/partitioned-popins/partitioned-popins.permission-self.tentative.sub.https.window.js.headers b/partitioned-popins/partitioned-popins.permission-self.tentative.sub.https.window.js.headers
new file mode 100644
index 00000000000000..0d61ec4d3e4c52
--- /dev/null
+++ b/partitioned-popins/partitioned-popins.permission-self.tentative.sub.https.window.js.headers
@@ -0,0 +1 @@
+Permissions-Policy: popins=self
diff --git a/partitioned-popins/resources/partitioned-popins.permissions-iframe.html b/partitioned-popins/resources/partitioned-popins.permissions-iframe.html
new file mode 100644
index 00000000000000..fe41057b7bb160
--- /dev/null
+++ b/partitioned-popins/resources/partitioned-popins.permissions-iframe.html
@@ -0,0 +1,20 @@
+<!doctype html>
+<meta charset="utf-8">
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+<script>
+(async function() {
+  test_driver.set_test_context(window.top);
+
+  // Step 3 (partitioned-popins/partitioned-popins.permission-{}.tentative.sub.https.window.js)
+  let message = "Success";
+  try {
+    window.open("/partitioned-popins/resources/partitioned-popins.permissions-popin.html", '_blank', 'popin');
+  } catch (_) {
+    message = "Failure";
+  }
+
+  // Step 5 (partitioned-popins/partitioned-popins.permission-{}.tentative.sub.https.window.js)
+  window.top.postMessage({type: "popin", message: message}, "*");
+})();
+</script>
diff --git a/partitioned-popins/resources/partitioned-popins.permissions-popin.html b/partitioned-popins/resources/partitioned-popins.permissions-popin.html
new file mode 100644
index 00000000000000..1009ee687a29a9
--- /dev/null
+++ b/partitioned-popins/resources/partitioned-popins.permissions-popin.html
@@ -0,0 +1,12 @@
+<!doctype html>
+<meta charset="utf-8">
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+<script>
+(async function() {
+  test_driver.set_test_context(window.opener);
+
+  // Step 4 (partitioned-popins/partitioned-popins.permission-{}.tentative.sub.https.window.js)
+  window.close();
+})();
+</script>